The present invention relates to a battery charger for recharging a battery, and, more particularly concerns a battery charger with improved switching means therein for providing energy to the rechargeable units. The present invention further relates to a battery charger for recharging a battery pack unit comprising a plurality of batteries, particularly of the secondary cell type, and the battery pack unit itself.
Batteries and other electrical energy storage devices often loose their efficiency and ability to provide energy following a heavy drain during their usage. Accordingly, devices to recharge batteries, either primary cells (dry cells) or secondary cells (rechargeable), are well known for this purpose. Many battery chargers are designed to receive the unit to be recharged in the housing of the charger itself, rather than merely connecting the recharging device by cable or wire to the battery. This not only allows compact design, but also makes for neater packaging. Examples of this type battery charger are disclosed in U.S. Pat. Nos. 3,579,075; 2,780,766; and 2,505,614. It is noted, however, in the recharging devices disclosed in the above patents that the battery terminals generally contact an electrical contact which resiliently moves to further contact an energized element so that energy can be provided from the recharger to the battery. This energizing actuation is commonly employed and relies upon the spring-resiliency of the contacts in order to allow the electrical current to flow into the battery. Furthermore, the previously known battery chargers were concerned with merely recharging one battery for each pair of electrical contacts in the recharger. In other words, a single battery would be received between opposed electrical contacts for the recharging operation. In this regard, there is room for improvement in the field of battery chargers especially in the means for activating the energy supply for passage of the same onto the unit which is to be recharged; and, room for improvement in the ability to recharge more than one battery for each pair of electrical contacts which contact the unit to be recharged.